1. Field of the Invention
The present invention relates to a digital mixer which processes audio signals and, more particularly, to a digital mixer in which channel strips having rotary encoders are provided in a console.
2. Description of the Related Art
Conventionally, there has been a known digital mixer that processes audio signals inputted through a plurality of input channels and outputs them from a plurality of output channels. Such a digital mixer is generally provided with channel strips for setting parameters of respective channels for signal processing.
This channel strip includes controls such as a slider, a rotary encoder, and keys or buttons, which are different depending on the performance and price of digital mixers, to function as a control group for controlling parameters of a channel assigned thereto.
Besides, since the number of kinds of controllable parameters is greater than the number of controls included in the channel strip, it has been widely performed to selectively assign parameters to the rotary encoder and allow the rotary encoder to function as a control for controlling the assigned parameter of a channel assigned to the channel strip, so that a plurality of parameters are made controllable by one rotary encoder. On the other hand, the setting of the volume of each channel is frequently changed, and therefore there is a strong demand for easy changeability of the setting. Hence, to meet the demand, it is common to allow a slider to function as a fader that is a volume control.
A plurality of channel strips are often provided side by side to make it possible to control parameters of a plurality of channels at the same time. It is difficult, however, to provide channel strips as many as channels the digital mixer handles. Hence, it is actually performed to prepare a plurality of layers that determine assignments of a channel to each of channel strips, and selectively switch the layers to switch assignments of a channel to each of the channel strips, thereby enabling parameters of a number of channels to be controllable using relatively few channel strips.
Further, since the digital mixer handles signals in pairs as L-, R-signals for a stereo, there is a demand for linked control of some parameters of two channels. Accordingly, it is performed to make a pair of channels which are assigned to a (2n−1)-th channel strip and a 2n-th channel strip where n is a natural number, and when a parameter of one of the paired channels is changed, the parameter of the other channel is changed in conjunction therewith, as for some parameters of a compressor, an equalizer, a volume level, and so on.
As a method of setting pairs, there is another method in use which makes a pair of a channel that is assigned to a channel strip in a (2n-1)-th layer and a channel that is assigned to the same channel strip in a 2n-th layer. This method enables the parameters of the paired two channels to be controlled by one channel strip, thus providing efficient use of channel strips. When the channels of the adjoining layers are paired, these layers are said to be in an obverse-reverse correspondence, and when one of the layers is selected, the selected layer is called an obverse layer, and the other layer is called a reverse layer.
In such a background, the channel corresponding to a channel strip in the obverse layer and the channel corresponding to the same channel strip in the reverse layer are in a correspondence for a user to be easily recognized. Therefore, there has been a demand for simultaneous control of the parameters of these channels by controls included in one channel strip. Further, this demand is particularly strong for volume setting.
For example, when recording is performed with a multitrack recorder being connected to a digital mixer, it is demanded to adjust parameters by one track and send them to the recorder, input signals which are returned by the recorder for verification into the channel in the reverse layer, and adjust the signals in level to the volume for easy listening and monitor them.
A conventional digital mixer, however, has a problem that controls of each channel strip can control only parameters of a channel which is assigned to the channel strip and therefore fails to meet such demands. This is true even in a case where the parameters can be selectively assigned to the controls.